lecture one

SOC 222 – MEASURING THE SOCIAL WORLD
INTRO to the COURSE Session #1
COURSE INFORMATION
Job Skills: Statistics and Data Analysis
Statistics: mathematical procedures that allow you to draw conclusions about your data
Data Analysis: Using data and statistics to answer specific questions about the world
Stats Anxiety
Read chapter 2 in stats for the terrified text
Rusty Arithmetic?
**All squared numbers are positive
(-x) = x 2
2
32 = 9
-3 = 9
Also check summation rules
∑
How to add up what follows the summation sign
SPECIFIC COURSE INFORMATION
1. Lectures and tutorials
• Session outlines posted each week • Tutorial start time:
• Tests in each tutorial
• Password
• Must attend the tutorial you registered in
• Tests conducted on BlackBoard
• Tests timed: 30 minute maximum
2. Questions
3. SPSS
CONTEXT of TODAY’S SESSION
Today’s Objectives: Know
1. The four different levels of measurement
2. Rounding numbers
3. Significant digits
4. How to open an SPSS Data Set
5. Variables and cases in a data set
6. Difference and use of Data View and Variable View
7. Difference between Variable Name and Variable Label
8. How to get a frequency distribution
9. How to get a scatterplot
Terms to Know
Statistics
Data analysis
Levels of measurement
Ratio variables
Ordinal variables
Nominal variables Dichotomous variables
Significant digits
Trailing zeroes
Leading zeroes
Research question
Independent variable
Dependent variable
Frequency distribution
Scatterplot
Positive and negative relationships
LEVELS of MEASUREMENT
What is “level of measurement”?- covered in both texts, pg.17-20 and 31-33- limerman is better
Numbers can be seen in 4 different levels
Ratio
• Counts or quantities – ex. Age in years, age in days, hours ect.. all ratio measures.
Number of courses a school offers, number of cities in Ontario ect…
• Meaningful “zero”- means none
• Math:
• Add, subtract, multiply, divide – can do arithmetic with them, because of the
meaningful zero
• Rank order
• Compare
• Ratio indicate the amount and quantity
Ordinal
• Relative quantities
• Math:
• Rank order (1, 2, 3..)
• Compare – can compare persons or things, who has more who has less
• Indicate rank orders, bigger number means there’s more and smaller means there’s
less, there’s order • Occupational risk- how much chance of something happening to you being in that
occupation
Nominal
• Similarities and differences
• Math:
• Compare
• No ranked order, all we can say is if they’re the same or similar or different
• Ex. If you assign numbers to religions that’s a nominal
• Mathematically all we can do with these numbers is compare them
• Just indicate whether two cases are the same or different
Dichotomy
• Only two categories – male or females, yes or no
• Can be simplifications
• Math:
• Add, subtract, multiply, divide
• Rank order
• Compare
• We can treat them as nominal or as ordinal
• Can also be treated as ratio measures- you can say you have it or you don’t, if you
don’t then you have measure of zero- there’s natural zero point
• Can be REALLY useful in stats
• Called DUMMY variables
Why Does This Matter?
• Stats involves mathematical operations, what you can do with them depends on their
measure
• What you can do with some numbers are different than what you can
do with others
• Level of measurement-
HANDLING NUMBERS Rounding
Significant Digits
Leading zeroes
Trailing zeroes
RELATIONSHIPS
Research question
Independent variable
Dependent variable
USING SPSS
1. Opening a Data Set
Here are the steps for opening and running SPSS from a computer lab:
1. Turn on computer & monitor screen (if dark, press any key)
2. CNTL-ALT-DEL to log on with your username and password
3. You get a welcome screen, “Preparing your desktop…”
4. Three ways to get to SPSS:
1. Click on an SPSS data set to open it.
2. Open SPSS first
5. If you get a “Windows Script Host” notice window, just close it.
6. SPSS starts and gives you a Welcome Window. Delete it. 2. SPSS Data Sets
A data set consists of rows (CASES) and columns (VARIABLE